Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 437,492 for the unitary authority in 2013, and a surrounding Larger Urban Zone (LUZ) with an estimated 1.07 million residents in 2007. It is England's sixth and the United Kingdom's eighth most populous city, one of the Core Cities Group and the most populous city in South West England.The city received a Royal charter in 1155. It was part of Gloucestershire until 1373 when it became a county in its own right. From the 13th century, for half a millennium, it ranked among the top three English cities after London, alongside York and Norwich, on the basis of tax receipts, until the rapid rise of Liverpool, Birmingham and Manchester during the Industrial Revolution in the later 18th century. It borders the counties of Somerset and Gloucestershire, and is also located near the historic cities of Bath to the south east and Gloucester to the north. The city is built around the River Avon, and it also has a short coastline on the Severn Estuary, which flows into the Bristol Channel.